Could Be Worse
by Silvershadow471
Summary: In which Reigen learns not to let psychic powers mix, lest something unexpected happens. Like finding himself looking at his own emotionless face through his disciple's eyes.
1. Chapter 1

**This takes place after the events of the anime. I might use one little thing brought up in the Mogami arc of the manga later on, but no plot spoilers.**

 **(Sorry to everyone who followed me for my Assassin's Creed fic; I'm getting to the next chapter. Mob Psycho 100 is just too good to** _ **not**_ **write about.)**

* * *

Maybe they should get out of the office more.

Usually the clients that came to the Spirits and Such Consultation Office had a problem or specter already in mind that they wanted dealt with as soon as possible. From there, it was at most just a trip to and from the specified site.

However, today's job was more akin to private detective work, and they couldn't actually start until they found the person they needed to tail. For now, Reigen Arataka and his student, Mob, sat outside a café, respective cups of coffee and milk in hand.

They had been sitting there in comfortable silence for half an hour when Dimple found them. It was getting to be late afternoon, but the weather was still nice enough that it wouldn't be too brisk for a few more hours. In Reigen's expert opinion, it was optimal outdoor café season. He was almost about to forget they had someone to look for before a familiar and obnoxious voice assaulted his eardrums.

"Oi, oi, don't you two have some sort of fake business to uphold?" asked Dimple, floating around the pair and peeking at their drinks. "Or is this some kind of day off?"

"No, we have a job. We're waiting for someone," Mob explained, waiting for the spirit to drift away from his cup before he took another sip.

Dimple scoffed. "Well, that's descriptive. Is Reigen attempting to teach you how to pick up chicks or something?"

A faint blush highlighted the boy's face, and he kept his cup to his mouth in an attempt to hide it. Reigen didn't notice as he waved a hand. "I actually do make money, you know. And we do have a job today: We have to tail a suspicious figure and intervene if they prove to be dangerous."

"Yeah, you're still on the vague side of this whole explanation thing…."

Setting his coffee on the table, the con man unfolded a sheet of notes from his pocket. "Earlier today, our client came by, uneasy but not terribly distressed. She said that a few days ago, her husband came home from work 'a changed man.'" He tapped his finger against the quote on the page. "He hasn't been keeping up his routines or habits, and more change every day. She hasn't noticed anything suspicious around home, so she thinks one of his coworkers must've cursed him."

"That's a pretty bold jump there," the ghost mumbled, looking bored but reading over the page anyway.

Reigen shrugged. "We've had jobs on less. I told her we'd scout out the area and see if there's anyone with that kind of power around. If it's nothing, then at least we discovered a pretty decent café, right, Mob?"

Mob nodded.

Dimple _tsk_ -ed and looked up at the other side of the street. It seemed to Reigen that the spirit was perpetually at a state somewhere in between disinterested and annoyed, so this was no different. A moment passed before he realized the spirit was actually watching something in particular. With a bobbing motion that passed as a nod, he asked Reigen, "That the office over there?"

"Yep." The nod had gestured to the multi-story building across the street, one that was as indistinguishably corporate as they come. "Our suspect should be finishing up work there soon," added the blond as he brought his coffee to his lips again.

Dimple was quiet. Uncharacteristically so. "Shigeo, is he weak or just far away?" He didn't look away from the building.

"He could be no minor threat," Mob mumbled. He was looking in the same direction.

Reigen slowly put his coffee back on the table. So there really was a psychic here? Guess it probably was the real deal after all. Just more work in the end, really. He checked his phone. "The regular work day ends in fifteen minutes, so when he leaves, we'll tail him—"

"Ah, scratch that, P.I. Reigen, feels like he's leaving now." There was something about the way Dimple said that that started to set him on edge. Was it confusion? Nervousness, even…?

They watched the stream of people entering and exiting the office building for one minute, then two. Then one stopped in the middle of the sidewalk and turned.

"Shit!" the ghost hissed. He darted behind the teen. "I knew he seemed familiar! That's the poor bastard I possessed for the whole religious cult business!"

Reigen raised an eyebrow. The man on the sidewalk hadn't moved. That was a good sign, right? The situation hadn't escalated unbelievably fast yet, as fights between espers usually go. "Maybe it's coincidence?" he offered.

"Nu-uh, doubt it. Shigeo's been sitting out here for what, an hour? He would've definitely sensed him, but he only came out when I got here." Dimple sunk further behind the café chair. "I doubt he's happy about that whole event…."

Mob still held his cup, but he didn't move to drink any more. "Can he even remember being possessed?" he asked.

"If his powers grew this much stronger during that month, then yeah, maybe. He's still standing there, after all." He took a quick glance over the boy's shoulder. "Yep. Can't even run," the ghost muttered. "He knows I'm here now and looks ready for a chase, and _damn_ , he's going to be pissed. Any sane person would be, after all."

They were just talking about how weak that guy could be, and now this? Reigen checked that the man still hadn't moved. "If you're so scared, then go hide somewhere," he proposed. Honestly, having Dimple in this state of mind was starting to make him uneasy as well.

"Oh yeah? And where can I hide that he won't be able to sense me, genius?" Dimple shot back.

"Alright, calm down. It doesn't even seem like that big of a problem right now."

And then, suddenly, everything just _stopped_.

Everyone in the immediate vicinity, first the pedestrians, then both lanes of traffic and the café patrons slowed to a stop. They stood or sat, unmoving, unbothered.

And through it all, the man across the street started walking toward them.

Breath hitched in his throat, Reigen amended his statement with, "Alright, okay, maybe now it's looking suspicious."

Mob set his cup on the table. "Dimple," he said quietly with a glance over his shoulder, "would my powers be able to hide you in me?"

An alarmed "Huh?!" came from the pair. "Hide me?" the spirit exclaimed, darting under the table so he could look the boy in the eye. "Damn well they could, but I can't even get through them to possess you in the first place!"

Biting his lower lip, Reigen watched the offending psychic stalk across the street, now most assuredly coming for the three of them. Everyone else on the block was still frozen in place, staring blankly ahead, completely complacent. It definitely could be some form of mass hypnosis, he figured.

There was a clattering behind him, almost making him jump out of his chair. All the other patrons had stood up in unison, pausing only a moment before shuffling away from the café.

That officially made this unsettling.

"What about me?" the con man suggested before he could convince himself otherwise. "If he's really after you, then I can suppress my abilities enough to be possessed."

"And how's that going to work, dumbass?"

"Then let me hear your better idea, 'cause you're getting thrown to the dogs otherwise."

The man was on their side of the road now, close enough to see he did not look friendly. Dimple saw this and grimaced. "You're doing the talking," he said, the only warning Reigen got before something cold hit, then _seeped_ into his chest.

He gasped, more from the shock of it than the cold, as the feeling disappeared as quickly as it came. A small shiver ran down his back, his shoulders stiffened, and a light pressure seemed to push on his head. He also could feel heat gather on his cheeks, probably lighting up the vicious red blush that appeared on the spirit's hosts.

Nothing really felt different, though. He was going to double check that Dimple had really vanished when in between his ears there hummed, _Jeez, you're tense._

 _I wonder why,_ he retorted with a thought. Whether that was how this telepathy worked or not, he didn't know, but he did know that their suspect was within earshot now. Painting one of his signature smiles on his almost uncomfortably warm face, crossing his arms, and leaning back in his chair, Reigen called out, "That's some fancy hypnosis you've got there."

The newcomer stopped some feet from their table. His cool gaze considered Mob momentarily before settling on Reigen. "What are you… _two_ doing here?"

"Enjoying a drink at this fine establishment. Have you come here before?" He lifted his coffee and inclined his head. "Some good coffee, if I do say so myself. It's a shame everyone else had to leave when they did."

That elicited no visible reaction. "You've been sitting outside my office building for too long to be normal. Add to it the fact that you're psychics, and it becomes suspicious. So. What do you want?"

Reigen's smile shrunk. He took a long, deliberate sip of coffee before asking, "What are you hoping to achieve through hypnosis?"

"What's it to you?"

"You shouldn't use your powers on other people," Mob said, head tilted ever so slightly so that he was looking through his bangs. It added enough of an edge to his monotonous words to make the man frown and shift his weight. The boy made his master proud.

"I shouldn't, eh?" the psychic echoed. "What's a few missing minutes out of their lives? Maybe one less decision they have to mull over? Where's the harm in that? After all—" He grimaced. "—it's not like they're having their free will stripped from them for over a month, right?"

"So you remember," Mob mused.

"Damn right, I do!" He dropped his hands onto the table, spilling the last bit of Mob's milk onto its surface. "Not all of it at first, but my life has been uprooted so much that it wouldn't even matter if I remembered!" His fingers curled around the edge of the table. "And I _know_ the evil spirit that did that is hiding here somewhere!"

Reigen had had enough. They could deal with a company man on a revenge-driven power trip when Dimple wasn't around to complicate things. He downed the last of his coffee and set it down with as much of a clatter as a paper cup could muster. "This sounds more like a personal issue than what we were paid to deal with. If you promise not to mess with people anymore, then I think we can just be on our way."

He made to get up but stumbled. His legs felt weak, and his feet sluggishly took a few steps to balance. "Shit," his lips hissed, "not used to—"

Reigen snapped his mouth shut. He hadn't said that.

… _backseating,_ Dimple finished lamely in his thoughts.

Across from him, the psychic straightened up. "Still taking vessels, I see," he commented, anger on his face, resolve in his voice. A dandelion yellow aura blurred into view around him.

One last shot to save this. "No, no, it's just my new shoes," he said easily, hoping the sweat on his brow wasn't visible. "You know how it is; always takes some breaking in before—"

"Let's see your face, you son of a bitch."

A bright golden hand thrust out a couple feet from him, and yet Reigen felt something grab his hair. He heard a shout from someone—maybe himself?—along with a bright blue flash, and then that something _pulled_ , and pulled hard.

It yanked him to the side, where it felt like he immediately slammed into a solid wall. He gasped, the impact rippling through his body. Instead of sliding down the wall, though, he fell, tripping over a chair onto the ground.

He ached all over, which is not what crashing into something should result in. In fact, now that he thought about it, they were in the middle of a cluster of tables; there were no walls around them….

Everything was blurry, but from his vantage point on the ground, he saw a speck of green dart toward the mass of black, white, and yellow. Dimple and the other psychic, probably? Reigen blinked a few more times before he could clearly see the man, cheeks red and aura ablaze.

"Ack, no no no no, ah, fuck!" he was saying. "God _damn_ , you got strong! Screw this, I'm out!" Dimple vaguely pointed at Reigen and added, "Catch you later!" before flying out and up over the roof, out of sight.

His former host stumbled back, powers getting even brighter as he frantically looked around. With the green pest gone, though, he glared at Reigen one last time before he turned heel and ran.

He let out a sigh of relief. The con man laid like that, on his side on the concrete, until he heard the rumble of traffic start up again. The ache was still there but dissolving at an astonishing rate. Well, he supposed that could've gone worse. He rolled onto his back, debating with himself over whether he should really charge his client for this probably incomplete job when he heard a quiet, "Shishou?" from his side.

"Hm?"

"I think there's something wrong."

"How do you mean?"

Reigen paused at the higher pitch of his voice. He cleared his throat and tried again. "What do you—"

He froze this time. That's not what he sounded like. Thoughts beginning to race, he took a deep breath, which is when he noticed the black at the edge of his vision shift away. That wasn't concussion-induced darkness, he realized, it was just dark. A dark-colored something that acted a lot like hair.

He reached an arm toward the sky. The sleeve was black, the hand much too light and soft and definitely not his. Something clicked together, and it locked into place when a _much too familiar_ face appeared over him, sandy blond hair shading dull, lidded eyes.

He took another breath. Exhaled. "I think I'm gonna have to agree with you on that."

* * *

 **I love this show, I love this story, I love these characters. Oh man. Maybe my new favorite anime right here.**

 **I also love body swap stories, and there are disappointingly few for MP100, especially given that it's about kids with ESP. I guess it's a small fandom, but still. After probably failing my thermodynamics exam, I needed something to cheer me up, so here we are: new fanfic started.**

 **Probably going to post this on AO3, too. I prefer FFnet, but AO3 has a bigger Mob Psycho fanfic archive. Granted, it's mostly smut (like everything on that site…) but there are some good ones that aren't. Might I suggest** _ **Switched**_ **by sancti and** _ **a strange but quiet morning**_ **by MajorasTrash? They're also platonic Mob n' Reigen swap fics, so if I take too long to update, you could always check those out.**


	2. Chapter 2

It was a good thing there wasn't anyone else at the café anymore. If there were, then they would think a middle schooler and a business man collapsed on the concrete weird.

Hopefully no one else showed up either, because it didn't seem like they were going to stand anytime soon.

Reigen sat up, holding his hands out in front of him. They were pale, uncalloused; he rubbed the fingertips together, trying to remember the last time his hands felt so soft. Black shirt, black pants, white sneakers, all of which were familiar but shouldn't be on him, let alone _fit_ him in the first place.

He had experience with the supernatural and knew way more psychic children than the average adult male. However, their powers didn't usually affect him directly. Sometimes he floated, but that was manageable. This was so different that he didn't know how to even begin to go about it.

What he did know was sitting in stunned silence was getting him nowhere.

"I'm…." He was caught off-guard again when the syllable was higher than expected. It only helped drive the situation home. "…not in my body."

"Yeah…," came the drawn-out agreement to his right. Reigen knew who he would see there. He took a moment to compose himself before looking.

He looked like Reigen Arataka. In some ways, it could be considered that he _was_ Reigen Arataka, in everything but composure: sitting on his knees, hands folded in his lap, back perfectly straight, dark eyes staring in a half-lidded manner that dashed any intensity, and the only hint of emotion being the perspiration beginning to coat his forehead.

He was too stiff and formal and calm and indescribably Mob and so _not right_.

On reflex, Reigen shied back. "A-ahh, I'm sorry, Shishou!" Mob stammered at the action, innocently holding his hands up, somehow sitting even straighter than before. "I d-don't think it was my fault, but if it was, then I didn't mean to!"

Even though it sounded a touch different, that voice was still plenty recognizable. Except his confident silver tongue was instead quiet, shaky, and entirely from the head. Not like him at all, Reigen thought. He managed to catch himself before he wrinkled his nose in unease. After all, he was the adult in this situation, even if it wasn't entirely literal at the moment.

"Hey, hey, it's alright," he reassured, waving a hand for emphasis. "I believe you. You're too good with your powers to do something like this on accident, and I doubt you'd want my job enough to resort to body snatching."

A small frown and a furrow in his brow appeared on Mob's stolen— _borrowed—_ face, an expression Reigen often saw when the child was attempting to think through a joke. It was such a Mob thing to do. This would be just another everyday interaction between them if Mob wasn't blond and older and in a suit and _him_ and—

Reigen shook his head and restarted the conversation. "What do you think did happen?"

"Well…," hummed Mob, eyes drifting upward in recollection. "Even though he seemed pretty angry at Dimple, it didn't feel like he was using enough power to exorcise him."

It was too weird. Some kind of morbid curiosity kept him watching, noticing every little movement and having to remind himself that it wasn't a reflection he was seeing. When Mob looked back at him, it became just too much. His stomach turned uncomfortably, and he looked away, down at his hands, as a slight shiver wracked his frame. His hands were still too soft. "He must've been a pretty lame psychic if he couldn't even exorcise one measly wisp of a ghost," Reigen said a touch absently, again intrigued by how his thumbs seemed to glide over the pads of his fingers.

"No, he could have done it," his student assured. How was he so calm right now? Reigen highly doubted this was commonplace, even in the esper community. "Instead, maybe he was just trying to exorcise him from your body. He wouldn't need as much power for that."

"Seems like he caught more than he was fishing for," Reigen mumbled.

"Maybe. Then I remember setting up a barrier, but after his powers hit, I found myself in here." Mob flexed a hand, using the other to fiddle with the cuff of his suit jacket. "It's…odd."

"That's one word for it."

"It's…."

As he searched for the term, Reigen noticed Mob's hand rotated, drawing small circles in the air. Did Mob always do that? The con man decided that no, no he didn't; Mob wasn't expressive in words and definitely not in gestures. "Disconcerting?" Reigen supplied. "Uncomfortable? Perverse? Intrusive?"

"Weightless."

"Oh…eh?"

"My powers always feel heavy, like there's too much. Like that's what's keeping me on the ground. But now, it's not overbearing. There's barely anything." Mob's tone changed at the end, the pitch higher. He smiled.

Barely anything? A quick wave of panic hit Reigen. "Wait, do you have _any_ of your powers? Where did they go?"

The psychic lifted his arm. A familiar kaleidoscope of blues and indigos faded into view and washed over the rest of his body, rustling his suit and hair with its unseen force. The table next to their spot on the ground rattled, and their forgotten beverage cups rolled off its surface, spinning and gliding on the shining air between them. "A little," said Mob. "But it's hard to direct, like I'm learning how to use them. Your body might still be trying to block psychic powers from earlier."

"Ah, yeah, that's a good point. Who knows how much was messed up." Reigen rubbed the back of his neck. Mob's hair felt shorter and silkier than his own. He was tempted to run his hand through the longer bowl cut on top of his head.

"What about you, Shishou?"

He snatched his hand back. "What about me?"

"How are your powers?"

"My powers…?" Reigen mused. Would he be able to use psychic powers in Mob's body? Palm upturned, he tried to recall what he had done back at Claw. It was so intuitive back then for that brief fight that he hadn't realized what had happened at first. So maybe if he tried to imagine the air around his hand becoming solid, sparkling with energy….

A moment passed where nothing changed; just two men sitting on concrete in silence, floating coffee cups between them. Then his palm prickled. It was subtle, but present enough that if he thought too much about it, it would be unbearable to not scratch it. He held his arm still and imagined that marbled ethereal light blanketing his limb.

Slowly, an aura pulsed into view, but it wasn't the one he expected. It was a red-orange, a dull burnt sienna. Slicing up the color, jagged and shifting throughout the air, were thin spikes of light pink and pale gold. It moved, rolling over and around his arm like water.

The dull ache in his bones reminded him of its presence, throbbing more than before, but Reigen was too entranced to notice. He did it. It wasn't quick, and his aura wasn't all that bright, but he did it. And it was so _easy._ He flipped his hand out to one suspended cup and pictured the color expanding to cover it. Instead, the cup shot away, missing Mob's head and flying into the road. But it was still a result.

The ache was getting uncomfortable. The aura disappeared when he willed it to, and he couldn't help the quiet "Whoa" that escaped with his breath. Is this what it was like for Mob every day?

"Mmm, seems weak, too," Mob observed, which—even though he'd been a real esper for all of fifteen minutes—prompted Reigen to cross his arms defensively.

"Hey, I'm not exactly in the best shape at the moment. This body was already sore when I got here."

"Sore?" asked his student, confused. "I don't think I was that sore. I don't think I'll feel today's workout until tomorrow."

"Oh great," the con man groaned sarcastically. "Then maybe I'm sore from hitting that wall. Although…." He glanced around, noting the significant lack of walls. "Maybe it was your barrier I hit?"

Mob blinked. He shrugged, dipping his head down and looking to the side.

The light tinkling of a bell sounded behind them. "Are you two okay out there?" a café employee asked, poking his head out of the door.

"Yes, we're fine, thanks. Just leaving, actually!" Reigen called back with a wave.

The employee frowned, turning his attention to Mob, the adult male currently somewhat hunched in on himself that he had probably expected to answer instead of the middle schooler. Either way, he nodded and retreated inside, again ringing the bell on the door.

"We should find Dimple," Mob suggested suddenly. "He might know more than us."

"Ah, good point. Then let's try the office first, shall we?" Reigen grinned, out of habit and support more than anything, and pushed himself to his feet.

Everything felt… _off._ The table seemed a little tall, the surrounding buildings a little too spaced apart. It hit him again: he wasn't in his 179-centimeter-tall proverbial shoes anymore.

Mob was moving to stand, but Reigen interrupted, pinching the bridge of his nose, "Wait, wait, just give me a second. Need to adjust."

He paused, half kneeling. Then he rose slowly to his full height. Reigen sighed before looking _up_ at his student. At his fourteen-year-old student stuck in his twenty-seven-year-old body.

Sometimes Reigen Arataka wondered what life would be like if he had a normal job.

Eyebrows raising slightly in realization, Mob looked back, taking in the small pout and narrowed eyes under black bangs, an expression that was almost definitely foreign to the young face. Reigen held their staring contest as if to challenge him to comment. He didn't.

He cautiously lifted a hand, hesitating before dropping it on top of Reigen's head. Neither of them moved. Then Mob gave his hair a light ruffle, and a small smile tugged at his mouth.

Reigen tried to stay defiant, showing his rejection of the demeaning gesture, but it didn't last long. A laugh escaped him, soon dissolving his composure into a bout of snickering. He pushed Mob's hand away and picked up the boy's schoolbag from under the table. "C'mon, _Shishou_ , let's get back to the office."

* * *

 **Wow, Mob is hard to write.**

 **I have two quizzes tomorrow. Er, today. It's 5:30 AM. Four finals, three homework assignments, two job interviews, and a commission to do in twelve days. What am I doing with my life. Writing this, I suppose.**

 **As an engineer, maybe I should regret spending so much time writing, drawing, gaming...**

 **Nah.**


	3. Chapter 3

The fifteen-minute walk back to the consultation office seemed longer than the original walk to the café. Maybe, Reigen thought, it technically _was_ longer, considering his legs were shorter than they were earlier.

Musings such as this buzzed through his head as he strolled next to Mob. He led the way, not paying any mind to his professional sort of saunter, one hand in his pocket and the other hooking Mob's schoolbag over his shoulder. It was how he always walked (sans bag). However, with his newfound lack of height, he realized he started to fall behind.

He scowled at having to rush to catch up. Now they can't even walk correctly anymore? After all, Mob never had trouble keeping up with Reigen on a normal day.

A few minutes passed like this, silence hanging between them. Even though he was still feeling a faint thrum of lingering soreness from…whatever was the source, it gradually concentrated along his spine. He rolled his shoulders and shifted uncomfortably, finding that standing a little taller alleviated the excess pressure. Reigen understood that he wasn't using the body his habits were made for, but _walking?_ Just walking to a destination was going to be an issue now? The movies never addressed this….

Well, if ambling along like himself wasn't what this body wanted to do, then maybe he should try walking like Mob: collected, inconspicuous, proper.

It worked. It seemed weird to his mind, but physically it felt natural. Reigen frowned at the mild disconnect that caused.

He had fallen a few steps behind again, but having just found a comfortable gait, he didn't change pace. Instead, he focused on the man—or boy, really—in front of him. He was tall, a fact that only served to make Reigen feel short. His sandy orange-blond hair, while lighter in color than much of the country's populous, appeared darker than he remembered. Did his hair always look like that?

Well, maybe it did. Reigen had only seen his hair before in the mirror and in photographs, both of which could easily alter his appearance depending on the lighting. This, however, was the real deal.

Reigen's stomach turned. He was actually looking at the back of his own head. He was walking behind his own body. How many people could say they've done that?

He dropped his focus to the sidewalk. It didn't make it much better, as the feet landing in front of him in a steady rhythm were nestled in white sneakers. Right. Mob's shoes, not his. Mob's clothes, Mob's bag, Mob's hands even.

Mob's hair, too. Remembering his thought process at the café, he twirled a lock of hair around his finger. It was just as silky as he expected. He pushed his bangs back, running his fingers through the fluffy bowl cut. The early naggings of guilt made him pause. This guilt was an intriguing sensation he thought would never come from his hair—but then again, it wasn't really _his_ hair right now.

He shook his head, dislodging the roundabout train of thought as well as any tangles left in his hair. It happened, it's done, and being caught up in trying to process it wasn't going to help anyone. Focus on the positives instead.

At least they were acquainted already. Reigen didn't have to worry about leaving his body to a stranger of unknown trustworthiness. He also was a successful con man and knew enough of Mob's mannerisms that he could pull off a decent impression if he needed to. Mob's family might be tough to fool, but with anyone else, he'd just have to be quiet and keep any gestures and body language to an absolute minimum.

He also could use psychic powers. Whether it was because some of Mob's powers stayed behind or what, he didn't know, but he'd have been lying if he said he wasn't at least a little excited to have them. With a bit of focus, he called the warm aura into view around his hand, watching one of the ethereal golden spires roll over his palm.

Looking back at Mob's blond head, Reigen grinned; it didn't feel as easy as it would have on his own face. He spied the ends of sandy orange hair lying against pale skin and, trying to concentrate the psychic energy to his fingertips, flicked the air. The result was negligible, shifting his hair as if the force were no more than a light breeze, but it caught Mob's attention. He turned, briefly confused before dropping his gaze to find Reigen.

"Shishou?" he inquired, pausing a moment to let the shorter catch up.

Reigen waved him off. "It's nothing. Just messing around with the new, erm, _situation._ "

"Ah, okay."

They lapsed into another silence. The con man was beginning to get irked by the quiet as well as his much-too-stiff walk when his student asked again, "Um, Shishou, if I may…?"

Finally, some conversation. "What's up, Mob?"

Mob was distinctly looking away from him at the sidewalk, eyebrows slightly drawn together. After a moment, he said, "I don't think it's healthy for your muscles to have this many knots at your age."

He barely managed to stifle his laugh. "First Dimple, now you? Seems like everyone complains about my body but me."

"Ah, no, no!" Mob hastily apologized. "It's fine, really. I'm just concerned because you're still young, but I feel so much older like this."

How old was the kid, fourteen? "I'm twenty-seven, Mob," Reigen told him, hand splayed over his chest. "While still relatively not-old, that's still almost twice your age, which means you're physically almost one hundred percent older than you were this morning, so of course you feel it!"

At the mere mention of numbers, Mob's expression started to go slack, overworked brain only managing an "Uh-huh" while trying to process.

"The point is," summed up his teacher, coming to a halt under the 'Spirits and Such' sign, "of course you feel older; you're just not used to it. I am, though, and I assure you, it's fine."

Mob still looked unconvinced, rolling his shoulders a bit, but Reigen had a greater issue on his mind. "So, Mob," he started slowly. "If we don't get this whole thing worked out soon—if Dimple isn't here, or if we can't switch back fast enough—would your parents _require_ you to come home? Like, they wouldn't put up with you working a late shift and just staying the night with your trusty mentor so as to not worry them?"

"No, probably not. I have school tomorrow, and they wouldn't like it if I made such short-notice plans."

A quiet sigh escaped him. "That's what I thought," he relented before facing his office building.

He didn't even reach the door before Mob announced, "Dimple's not in there."

"You sure?"

Mob nodded.

"…What if we're both too weak right now to be able to sense him?"

Mob looked unconvinced. Reigen was also unconvinced, but they went inside and searched the office anyway. Four minutes later, back where they started, the ghost had unsurprisingly not been found, but at least they had put off the inevitable for a little bit longer.

Reigen steepled his fingers and took a deep breath. "Okay," he admitted. "Okay. Time for the ol' switcheroo." He pointed his hands at his attentive student. "You're going to have to go back to my apartment for the night. You've got my keys, my wallet, you know where it is; just take the train, and if you get lost, I can text you the address. Tomorrow, if you'd rather keep the office closed, I guess I can spare a day's worth of pay. Meanwhile!" He pointed back at himself. "I've gotta go relive my youth for a bit: do homework, go to school, family meals, all that."

"Should we tell Ritsu what happened?" Mob asked.

Ritsu. Oh shit, Ritsu. The kid already didn't like or trust him. If he found out what had happened to his brother under his supervision…

Maybe Ritsu wouldn't actually kill him when that would also kill Mob's body. Then Reigen remembered Ritsu was an esper now and much more creative than his brother; the older man didn't doubt the teen's ability to bypass physical damage yet still cause harm. "No," he announced. "No need to drag him into this as well. He would only worry about you."

His student didn't look happy about that decision, but he didn't object. He watched Reigen for a moment before his eyes drifted to the darkening sky. "I guess we should go soon."

"Yeah…." He could feel the beginnings of perspiration on the back of his neck. Despite his nerves, though, he clapped a firm hand on his disciple's shoulder, noting how he did not like having to reach up to do that. "Don't worry about it, Mob," Reigen told him with a smile. "You're an adult now, so play the part. You can do whatever you want."

Mob took a deep breath. He nodded. Then he mimicked Reigen's smile, making it look more like a half-smirk on that face. "Right you are, Mob," he agreed with just a touch more volume.

 _Wow_ , that's unsettling. He let go of his shoulder and laughed, if only to hide the discomfort. "Ah, alright then. Off to a good start, I see. So on that note—" Reigen slipped Mob's bag over his shoulder, tapped the toe of his shoe against the ground, and lifted a hand. "Good night, Shishou."

"Good night."

They parted, Mob going back the way they came toward the station. Reigen had brought Mob home a couple times when the boy was younger, so he was hoping he still remembered the way. It wasn't too far from the office.

The ache threatened to settle in his back again before he straightened up, grumbling all the while. He's a grown man, having been walking his whole life, and _now_ he has to completely readjust everything. Can he not? He's psychic now; can't he just float?

He stopped, looking down at his feet. What if they were…not on the ground? Mob's white sneakers were starting to glow orange before he snapped his head up and continued walking at a brisk pace. "Nope, no, bad idea, very bad idea. I swear, I'm going to get this kid killed with my antics, and he isn't even here this time."

Caught up in trying not to be tempted to weigh the risks involved in testing various psychic powers, Reigen was at the Kageyamas' front door in no time. With a huff, he relaxed his face. Mob was calm. Mob wasn't emotional. And this is Mob's own family. _Be as boring as anything, Arataka,_ he told himself.

He opened the door to find Ritsu standing just inside the hallway, holding a hand towel. "Oh, there you are, Nii-san!" he said. "You're home late."

Reigen swallowed before giving him a small nod. Voice flat and even. "We had to go a bit further into town for our job today."

Ritsu looked at him. Then a small smile appeared. "Well, you're back just in time. Dinner's on the table when you're ready."

"A-Alright."

The boy continued into the kitchen, leaving Reigen to release the breath he didn't know he had been holding. _Okay, not bad. C'mon, you're a con for a living! This is just lying with a bit of acting behind it. You got this._

He hesitated, just a second longer, before he untied Mob's shoes and left them with his bag by the door. Brushing at his hair and adjusting his cuffs for good measure, he followed his 'brother' to the kitchen.

* * *

 **Alright, not where I was going to end it, but this went longer than expected, and next part is also long, so here ya go**

 **On another note, if you're lookin' to read some ?% AUs/theories, I've got two up right now over on AO3 under the penname Silvensei. Let's see how long I can keep this writing streak going!**


	4. Chapter 4

**how the hell has it been four months since the last update what is time**

* * *

It was a regular, completely normal house: Hardwood floors, pale colors and earth tones, professional and childhood art hanging on the walls, an open room split into a kitchen and a living room by a simple four-person dining table…. The house of a normal family. How did the world's most powerful psychic come from this place? It seemed wholly anticlimactic, if you asked him.

Peeking around the corner, Reigen saw Ritsu pulling out a chair from the table across from a man sipping a beer. Mob's father, he realized. He had only briefly met him once a few years back and knew next to nothing about him. Couldn't even remember his name. Well. Guess he should learn a bit more about this little family in his current situation.

A woman—Mob's mother—set two more plates at the table in front of the remaining chairs. She cast a curious look at Reigen before he remembered he was still standing in the hallway. With a start, quickly— _but not too quickly_ , he reminded himself—he took the last seat, unfortunately less than two feet from the most overprotective and spiteful middle schooler there was.

He swallowed. Never was he more glad that Mob wasn't the type to begin conversations.

Curry was on the menu tonight. It actually looked pretty good. Ritsu was already eating, so he scooped up a spoonful, from right where sauce met rice, and popped it in his mouth. Mmmm… he almost moaned from the bliss of it. Sweet curry sauce with just a noticeable kick, tender chicken, warm rice; he couldn't remember the last time he had a classic home-cooked meal like this. How dare his student not invite his beloved teacher over for dinner.

The taste was gone all too soon. He took a second spoonful, then a third, until a chuckle made him freeze. "Got a hot date to get to, Shigeo?" the boy's father joked.

"Uh." Honest but soft-spoken, right? "It's just really good," he admitted, dropping his gaze to his plate.

Reigen intentionally avoided looking at them and couldn't gauge their reactions, but Mob's mom laughed, admiring how "someone seems to appreciate this household's cooking" and inciting a round of friendly bickering between the couple. Ritsu said nothing. Reigen hoped the eyes he felt watching him were just a product of his paranoia. He couldn't have been in this house for more than five minutes; there's no way this kid could already be suspicious.

At least he wouldn't do anything in front of his parents. Probably. Plus Reigen still had curry to finish. He chewed his next bite more slowly, savoring the warm flavor.

It was still pretty warm. In fact, it was so warm that there could've been steam coming off it not too long ago, yet he could eat it just fine. Didn't burn his mouth at all. Huh. Maybe he really did have a cat's tongue….

 _Not at the moment, I don't,_ he thought, allowing himself a hint of a smile before his next bite. Delicious. Some kids really don't know how good they have it.

It was gone all too soon. Ritsu talked about his day and student council affairs for much of the meal, so the most Reigen had to do was nod every now and then. He should at least feel lucky he was masquerading as a quiet and reserved kid instead of some loudmouth. A quiet, reserved, incredibly powerful psychic kid.

Okay. Okay. This was terrible. Reigen knew that. He unintentionally body-snatched his student and was stuck in the throes of puberty. Mob was probably more awkward and uncomfortable than ever. But it would only be more awkward if word of this got out, so all they could do now was sit and wait. And if that meant the fraud had to put up with having real, convenient, awesome psychic powers, then that would be his cross to bear.

He sighed. If only psychic powers could make curry out of thin air…. He almost set his now-useless spoon down, but then he remembered: He was holding a spoon. He'd seen the Matrix. Spoons were like a rite of passage.

It looked just a touch large in his hand, the proportions of both being askew from what he was used to, and the blurred, distorted reflection in its surface lacked the bright glow of blond hair. He tightened his grip, pushing his thumb into its stem, but the metal wouldn't bend from such a meager attempt. Good. He focused on his hand, just like earlier, imagining that orange glow around him, making the spoon bend itself, using energy to move energy as there really was no spoon, or whatever.

A light washed over the utensil. Or maybe it was just the glare from the overhead light. Nothing happened as seconds passed. _Damn._ Reigen frowned. _This worked earlier…. On something lighter but still._

He shivered. Over the white noise of the family's conversation, something seemed…off. There was…actual white noise, or some kind of static, and once he noticed it, it tickled his ears. Another chill ran down his spine. What was that, poor reception? This wasn't a phone call. Sandpaper? Sugar in a sifter?

At that last thought, the grating feedback cleared, sharpening into the course sifting sound he had imagined, and like striking flint in a lighter that sunset hue sparked around his hand. The sound increased to almost a sizzle as the light hit the spoon, flipping it once, twice, behind and over itself.

Reigen jerked away, biting back whatever uncharacteristically-Mob noise would've sprung out. Simultaneously a sigh and a laugh came from across the table. "Another one from your allowance, Shigeo?" Mrs. Kageyama commented, exasperated.

"I—" He let out a short breath. Initiation passed. He really was the One. His lips twitched, but he shot the grin down before it could fully form. "No, that's fair," he agreed. It _was_ his fault; the least he could do was pay Mob extra as compensation for the silverware after all this.

He looked up as Mob's mother shook her head yet said nothing more. Her husband chuckled again, using what sounded like the tried and true excuse of "boys will be boys". In general, though, they were uninterested. Even to this quaint little family, spoon-bending superpowers at dinner were _that_ commonplace? _…Well,_ he reasoned, replaying that last line in his head. This _was_ Mob they were talking about. And didn't the brother have powers, too?

Reigen spared a glance at Ritsu—and immediately regretted it.

The boy stared at him, eyes a touch wide to be normal and harmless. Spoon stuck over his plate, lips pressed into a thin line, he stared, and Reigen was caught like a deer in headlights. _Did I blow my cover already? But the parents didn't notice anything since the mother said 'another' like this was a recurrence, and this kid wasn't even paying attention to me, talking about grades or school shit! Please, God, whoever's out there, I don't need this angsty teen on my ass any more than he already is, just—_

"Ritsu?" the mother asked.

"I got it." And just like that, Ritsu plucked the deformed spoon from his hands, expression neutral. His hand shimmered in fragmented plates of cyan and cobalt, and the spoon neatly twisted itself back into a functional utensil.

That's not good, if his paranoia was already getting a hold on him. Taking a moment to steady his voice, Reigen asked, "May I be excused? I have a test tomorrow I should study for."

Her eyebrows raised, but the woman didn't object. "You can leave your plate at the table. If that's what's got you stressed, Shige, I don't want you breaking anything more by accident."

Her fake son hummed in agreement before attempting to look like he wasn't fleeing the scene of a crime. He pace only broke when he was in the hallway, almost swinging on the banister as he rounded the corner and took the steps in pairs, the clatter of metal against ceramic continuing until he was out of earshot. Sliding into the bedroom and all but slamming the door, he leaned his back against it with a breath of relief. Day one: Success.

Reigen wiped his forehead with his sleeve as he took in the room; the student seemed to perspire almost as much as the master. Neat bed, stocked bookcase, well-kept desk, uniform draped over the back of—oh. This must be Ritsu's room, he realized, tension returning. Good thing he left early, or else that could've been bad. After checking that the coast was still clear through the keyhole, he opened the door—hopefully as wide as it had been a minute ago—and sidled along the wall to the next doorway. Open, uncluttered, rolled-up futon, fewer books…. Yep. Looked like a Mob Room to him.

The door closed with a soft click. _Now_ the day's a success.

He sighed, letting himself relax for real this time, tugging at his collar to loosen his tie…which wasn't going to work because this wasn't his suit. Right.

His fingers fumbled to unbutton his uniform jacket. How long has it been since he last did that, twelve years? Thirteen? After wearing suits for so long with their smooth plastic buttons, the engraved metal of the gakuran felt foreign. Slipping it off his arms and throwing it onto the desk with grace, he caught himself before he once again tried to undo his tie. "Mother of…," he mumbled, flipping the futon open with his foot. "Damn force of habit."

He fell face-first into the pillow and wrapped his arms around it. To his at-this-point-nonexistent surprise, it didn't smell like his pillow at home. The hair around his eyes was too dark; his arms were too short to grab his forearms; his back didn't stubbornly hold onto the tension knotting his muscles. It seemed routine, but the more he payed attention, the more alien everything felt.

Reigen rolled onto his back. He was good at reading body language, but he never did it to himself. Now, though, the differences were striking, like when he folded his hands over his stomach and again marveled at how smooth they were.

There was something else to it, though…. He patted his stomach. Mob had always been slim, with not much to him at all, but it felt like he was starting to build some muscle. _Looks like all that training is actually paying off,_ he thought with a twinge of pride.

The ache from earlier was still there. He poked his abs, then his chest, feeling the renewed dulled pain of sore muscles. It felt like he—well, Mob—had worked out for hours yesterday, but the boy had seemed skeptical when he had mentioned it. He probably just fell wrong on the concrete at the café. Yeah. Not sure if there's a right way to fall on concrete, after all.

"Nii-san?"

Bolting upright with a squeak, Reigen threw his arms up towards the sound, flailing his hands in a vague semblance of martial arts. One of his hands had a pale, flickering aura around it.

Another knock at the door. "You left your bag downstairs. Is everything alright?"

Ah. It's fine. Just play it cool. "Oh, yes, I'm good," he announced, pushing himself to his feet. He paused just a second to appreciate how lithe and easy the action was. "Just wondering where I put that now. Thanks, Rit—" _slam!_

The door snapped open into his shoulder, throwing him backwards into the desk. A fist, balled in his shirt, held him there as Ritsu fumed above him. Mob's schoolbag hovered in the background, encased in a bubble of blue, and the door swung silently shut. _How's this kid taller than me?_ was the lone thought he had before his face was hit by a damp cloth.

He squeezed his eyes shut as Ritsu furiously scrubbed at his cheeks, his protests coming out as choppy monosyllabic discontent. It wasn't long, though, before it slowed. Reigen heard the boy say under his breath, "Not Dimple…?"

When Reigen blinked open his eyes, he was shoved against the desk again. "Where's my brother?" demanded Ritsu, low and dangerous.

He swallowed. Could he still save this? "Ah, Ri-Ritsu? What— uhh, I _am_ your brother?"

"Don't fuck with me," he hissed. "Who are you and where's Shigeo?"

Reigen looked away, breaking the death stare. "Jeez, kid, watch your language," he muttered on reflex.

He paused, expression losing some of its ferocity. "Reigen…?" He leaned back. "Reigen Arataka, is that you?"

"Ah…." A drop of sweat traced his jawline. "Now Ritsu, let's not do anything rash—"

He was yanked to his feet, two hands twisting his shirt, their noses almost touching. "My brother. Now."

"He's fine, he's fine! Ritsu, it's— He's probably having some ramen, watching a movie, watching TV, chillin' at my apartment— He's perfectly fine!" He laughed nervously, holding his hands up.

An aquamarine light burned around the boy, illuminating his eyes and further spiking his hair. The unique chiming psychic white noise that accompanied it was at the edge of Reigen's hearing. "What do you mean 'probably'? Why do you look like him?"

"Ah hah, ah, now Ritsu, don't— don't get mad— _urk_!" He choked, throat constricted. Psychic powers? Just his shirt collar? He couldn't tell. _"Ack, Rits—!_ Not— not _me,_ real—his body—!"

He was dropped back onto the desk, gasping for air. "Oh, thank god," he breathed. His head fell back; his bangs barely parted, stuck to his forehead. "This is exactly what I thought would happen. I don't know why I thought I could avoid this. Jeez, my back's sore again. So there's that. Wonderful."

Ritsu was staring at him, mouth agape. His aura didn't dim. Slowly, he asked, "This isn't a disguise…? You're… _possessing_ him?"

"No, I'm… well. Well, maybe. Technically. I guess. His body, at least. Mob's not in here. Bit of a _quid pro quo_ situation here. A _Vice Versa._ A _Freaky Friday_ , if you will. But on a Wednesday."

"You…." Ritsu shook his head. "You abandoned your student _and_ your body, just to come to dinner?"

"Hey, it was Mob's idea, you know. Didn't want his family to worry, although—" he looked at the increasingly judgmental teen, "guess that's one fewer we have to worry about. I kinda thought it would've taken a bit longer, though. How'd you figure it out so fast?"

Ritsu scoffed. "Are you kidding? You're nothing like Nii-san. Your aura's a completely different color, even. And anyway, here I was thinking you were a complete fraud. Turns out you're just incredibly stupid with your powers."

Reigen straightened up. "I resent that, you know," he said. _Along with the fact that you can look down at me._

"I don't care." He cracked his knuckles, an action that was made a lot less nonchalant when he said, "Now how about you tell me what happened this afternoon so I don't have to force it out of you?"

He nodded and opened his mouth before he hesitated. "But you wouldn't want to hurt your brother's body just to get to me, would you?"

The boy's expression darkened. "Espers don't need to use physical forces. You should know this, Mr. World's Greatest Psychic."

"Eh heh…."

A knock sounded at the door. When Mrs. Kageyama opened it, her son's aura had disappeared, and Mob's bag fell onto the futon. She barely considered it. "Ritsu, what are you doing? Your brother has to study."

"Yes, Mom." His stare didn't waver. "I guess we can talk tomorrow. On the way to _school_." When their mother was out of view, Ritsu pointed from his eyes to Reigen's, then spun on his heel and left, pulling the door closed with a shock of cyan.

…okay. Reigen let out the breath he'd been holding. Alright, not bad. Could've been worse. Thank you, motherly instinct. The muscles in his torso and arms were sore again from getting thrown around, but nothing a little rest won't fix.

He lay down on the futon. Maybe having Ritsu in the loop would be helpful: another set of eyes to look for the missing spirit; more powers at their disposal for whatever; plus the kid could be clever, more so than his brother. If he could just be a bit more rational about his brother complex, then he could be a good ally.

Staring at the unfamiliar ceiling, he wondered for not the first time what kinds of karmic turns his life had to take to end up as a fourteen-year-old esper worrying about middle schoolers beating him up.

He wondered if Mob was alright.

He could always text him. Would that seem overprotective, though? He wasn't _that_ worried; he was sure his student could protect himself better than most adults, and he had the added advantage now of _being_ an adult to boot.

It was still relatively early. Before Reigen could doze off, he sat up and grabbed Mob's jacket, finding the cellphone in the second pocket he checked. Selecting 'Reigen-shishou' from 'Recent Contacts', he shot off a quick message asking if he found his apartment without much trouble. He sat for a moment, watching the screen, then he sent another text asking for what homework he still had left to do. While waiting for a response, Reigen dug through the bag that fell nearby, looking for a notebook, pencil, and a reference from which he could forge Mob's handwriting.

* * *

 **Not really feeling this ending, so have an alternative:**

 **Ritsu: you gonna pay you jesus goddamn son of a whore  
** **Reigen: Uh, Ritsu? You're not going to hurt your brother's body, now are you?  
** **Ritsu: Sorry Dude _Tough Break_**


End file.
